Concrete pile.



PATENTED APR.. 21, 1908.

P. B. GILBRETH. CONCRETE PILE.

APPLICATION FILED MAB.1,1006.

n/ CAM/46), 13 536, W

A A/R [nvenzfar QZL MK 6' W WM witnesses (RM 7+ ff UNITED STATES PATENT OFFICE.

FRANK B. GILBRETH, OF NEW YORK, N. Y., ASSIGNOR TO CORRUGATED CONCRETE PILE COMPANY OF AMERICA, OF NEW YORK, N. Y., A CORPORATION OF MAINE.

CON CRETE PILE Specification of Letters Patent.

Patented April 21, 1908.

To all whom it may concern:

Be it known that I, FRANK B. GILBRETH, a citizen of the United States, residing at New York, county of New York, State of New York, have invented an Improvement in Concrete Piles, of which the following description, in connection with the accompanying drawings, is a specification, like letters on the drawings representing like parts.

My invention relates to concrete piles and improvements for sinking the same, being more particularly concerned with the shape and construction of such piles and means for sinkin the same.

My invention will'be best understood by reference to the following description when taken in connection with the accompanying illustration of one specific embodiment thereof, while its scope will be more particularly pointed out in the appended claims.

In the drawings,Figure 1 shows in side elevation, partly broken away, va pile embodying one form of my invention; Fig. 2 shows in plan a section on the line 2-2, in Fig. 1 Fig. 3 shows in sectional elevation and partly broken away, the pile illustrated in Fig. 1, together with the driving cap and jetting pipe in readiness for sinking the pile, and Fig. 4 shows a modified arran ement of the jetting pipe with reference to t e pile.

Referring to the drawings and to the embodiment of my invention there disclosed for illustrative purposes, I have shown a formed or molded pile A which, while of simple construction, has features which render it extremely efficient as a pile and other features which assist to a marked degree in the facility and rapidity with which it may be sunk or positioned in the ground.

The pile shown has a hexagonal cross-section and is provided with plane sides or faces a in which, and preferably symmetrically disposed with reference to the pile center or axis, are formed grooves or corrugations b, which are here shown as substantially or approximately half round in cross-sectional outline and extending for the greater part of the pile length, but actually terminated short both of the bottom and the top so that at the former there is left a base or leading portion 0 of the full cross-sectional area and a head or top portion (1, also of full cross-sectional area.

' The pile body is preferably tapered, as

' shown, with a uniform or gradual taper from the head end of maximum diameter to the leading end of minimum diameter and is also cored to provide a tapered central bore or jetting passage e to receive a jetting stream of water, or a ipe carrying the same to sink or assist in sinliing the pile.

Suitable reinforcement, both longitudinally and laterally, is provided in the form of a skeleton metal frame f com rising a series of lon itudinal members g wit bent or overturne .ends g, the said members 9 being secured at intervals to the hoo -shaped members hwhich act to bind or hold them together. The size and'numbcr of the reinforcing members will of course be roportioned to the service for which the ilb is designed. The reinforcement is pref rably carried as near the sides of the pile as the presence of the grooves therein will permit in order to embrace as much of the pile material as possible and is preferably in the general form of a truncated cone, ta ering with the pile from top to bottom. T e shape of the reinforcing member f still leaves portions of the pile lying adj acent the longitudinal-edges and between the grooves without local reinforcement. To strengthen these portions of the pile there may be and preferably are employed additional reinforcing members i, preferably metallic strips having bent ends. These are symmetrically arranged with reference to the two adjacent faces and closely adjacent to the intervenin corner or edge.

The form of plle disclosed is molded into the sha e shown and allowed to harden before sin ing, this molding operation being carried on either at the place where the piles are to be used or elsewhere whence they may be transported to the lace of use. Molds for the same are read y constructed out of lanking cut to the required dimensions and ined wlth rounded strips suitable to form the grooves. The mold is set up lengthwise on the ground leaving 0 en one or more of its upper sides through 'w ich the concrete is entered. The reinforcement is positioned by wiring it to the sides, or by suspension members entering through the 0 on upper side, or both methods may be emp oyed.

The central tapered core or mandrel is supported by the closed hexagonal end pieces of the mold through which it extends to leave a projecting portion at the head end of the mold. When the mold is filled with concrete the remaining u pler side of the mold is placed in position an t e pile allowed to set. After settmg from one to two days the mold is stripped from the pile and the latter allowed to harden for a further period, preferably for at least eight to ten days, when they are readyfifor use. sirable to supply moisture to the pile to facilitate the setting of the cement andthe piles at that stage are therefore referably covered with burlap or other suita le material which is kept saturated with water.

The described process of molding is not essential to my invention but in practice I have found it simple and eflicient.

Ordinarily there is experienced considerable difficulty finally withdrawing the central tapered core after the setting 0 the concrete. This difliculty I have wholly overcome by partially withdrawing the core when the concrete has partly solidified but before actually hardened or set. The extent of withdrawal will vary according to the degree of taper and length of core, etc. but in the illustrated instance when the concrete is in the first stages of setting the projected butt or head end of the core is given a partial turn and retracted a few inches. 1 This is sufficient to free it from necessary contact with the concrete and can be done at such a stage that there will be but'slight tendency for the concrete to settle or collapse. If it does settle or collapse, it will do so' against the still closely adjacent sides of the core and the latter may again be turned or twisted and retracted a fewinches further until finally it is entirely free from the then hardened concrete, leaving nevertheless a symmetrical and perfectly formed tapered bore. In practice the workman has merely to turn and slightly retract the bore during the early stages and thereafter repeat the operation once or twice and the core will be left free from the hardened interior of the bore.

The pile described when placed or ositioned for sinking may be sunk large y or wholly with.the aid of a water jet carried through the central bore 0, the latter acting as an induction passage either for the water or a pipe carrying the water. While the water may be delivered under pressure di rectly to the bore at the head end of the pile and discharged in the form of a jet at its lead ing end, it is preferably delivered b the laterally extending sup ly pipe 7' to t e removable jetting pipe connected thereto, the latter being of a diameter slightly less than the smallest diameter of the bore. The jetting pipe 7c preferably extends into and through the pile for substantially its entire length and has at its end the tapered nozzle 1, the contracted nose of which projects slightly beyond the leading end of the pile.

The pile having been ositioned and water under pressure 'delivere to the jetting pipe, the pile may be entirelysunk, if desired, by the erosive action of the waterjet formed at its leading end, or assistance may be had by During hardening it is de-' simultaneously ramming orotherwise forcing the pile at its head end, or such forcing action may be used alone. As certain features of my invention, however,-are-related rimarily to the jetting action, reference will st be made thereto, The water discharged through the nozzle forms a powerful jet which strikes the underlying earth, loosens or displaces it and then carries the earthy water u and about the sides of the pile, while the atter settles into the excavation thus progressively formed.

The facility and rapidity with which sinking is'effected obviously depends upon the erosive capacity of the water, and, slnce the erosive power of Water increases approximately with, the sixth power of its ve ocity, slight changes in the frictional resistance offered the water in its passage to and from the point of application of the jet will, for a given pressure head, strikingly affect the erosive efficiency of the jet and the rapidity of sinking.

In the illustrated embodiment of my invention, the metallic jetting pipe k provides an induction passage of minimum frictional resistance for the water passing to the nozzle. The water, if permitted, would naturally return to the surface either in a relatively thin film up the sides of the pile, encountering a relatively great frictional resistance or by forcing an irregular path of still greater resistance through the adjacent and dense earthy matter. In the case of the illustrated pile, however, the water returns up the side of the pile in the grooves or corrugations b,

which are so shaped and formed as to provide viding moreover, a groove of sufficient size and depth to permit' the Water to come up in several well defined, l compact streams. If

frictional resistance for a given capacity, prof the eduction passages :are too shallow or not sufficiently defined, they tend to clog and fill with earth as the pile settles and-the water is obliged to spread instead of forming a compact stream. This not only offers increased resistance to the water, but also results in tearing away and displacing the adjacent densely acked earth and gravel at the sides of the pi e, which, were it not displaced, could be relied upon to better support and sustain the sunken ile. l/Vith the surface eduction passages il ustrated, the water with the earthy matter carried thereby, almost wholly to the channels or passages provided and spurts up at the groun leve 1n welli defined streams.

The corrugations b, if desired, might be ex tended the entire length of the pile, but the absence of the grooves at the extreme leading end of the pile not only renders the entire axis.

resistance to the jetting water.

adjacent earth is such'that when the sinkin 1 section and thereby senslbl increase the s insection-of a regular olyglon and arrange a contact with the earth is first increased by cross-sectional area of the hexagon available as a base for the pile to rest upon, as well as rendering the pile less apt to fracture during handlin but the jet is thereby compelled to spread aterallyand is distributed more effectively and evenly at that point. Stopping the grooves short of the head end of the pile also results in strengthening the head somewhat, which is sometimes important where it. is designed to hammer or ram the pile.

Where jetting is employed it is desirable to avoid an eccentric jet formation which will tend to settle the pile obliquely, but on the contrary to' maintain a central jetting-action which will sink the pile vertically from its ini- "tially selected position. For this purpose it is desirablenot only to have the jet arranged centrally with reference. to the pile, but also to present a plurality of eduction paths of substantially equal resistance, symmetrically arran ed with reference to the jet, so that the jet wi I be maintained true with reference to 'the pile axis. .For this reason, amon others, K I preferably construct-the pile with t e crosssingle groove in each ace t ereof, the grooves being symmetrical with reference to the pile Other cross-sectional forms may be used when desired, but the hexagonal crosssection permits the formation of the grooves without unduly undercuttin the longitudinal-edges. It also permits t e reduction of the grooves to areasonable number, a oint of advantage since subdivision into a arge number of grooves materially increases the The puddling action of the water upon the has been com leted and the water draine away, the cart tends to settle in and about pile so closely that the skin friction upon atter is. greater than when the ile is shutting off the jet just before the pile is fu ly sunken and completing the sinking by the action of the hammer or other forcing means from above, which causes the pile to settle firmly in the adjacent softened earth. The grooves, however, notonly assist in sinking the pile, but act. to increase the perimeter of the ile or surface friction of the pi e, which in many instances must be largely relied upon to sustain the su ported welght. In the illustratedpile tlie formation of the ooves is such'that while sensibly increasing t e surface friction ofthe pile, there is left asolid body portion susceptible of effective reinforcement and well adapted to resist all strains to be met with, In connection with the cored in-' terior the grooved sides produce a particu v larly effective pile structure,- for, with a given quantity of concrete, the sul'face exposed to .pile. .tending slot 'n to admit the supply pipe 7 A hammer, or other forcing means, adapbt ed for simultaneous use with the jet, may

applied continuously therewith or used merely to finally settle the pile when the same approaches its sunken position. In either case, if a hammer is used, 1t is'desirable to interpose some cushioning means between the hammer and the head of the ile. In Fig. 3 I have indicated conventlonal by dotted lines the head H of the hammer, which may be of any suitable or usual construction. Between the hammer head, however, and the head of the pile is interposed a cushioning device which comprises the ea or casing m, of sheet iron or other suitable material, which for simplicity of construction may be made cylin rical in form. The casing 1s provided with an interior fixed diaphragm m by which it is supported upon the pile head through the interposition of a spacing block n, so that its de ending sides overla and loosel embrace t e endof the he spacer block has a laterally ex from the side, the casing also being cut away to clear the pi e. Within the casing and above the di'ap agm is placed a body of cushioning material 0 of any suitable nature, which, for example, may consist of loose ieces of rubber hose interposed between ayers of hemp or old rope ends. Upon the cushioning material rests the wooden plunger block p loosely slidable in the u er 0 en end of thecasing and surmounted y t e iron follower q in which is central y seat-ed the wooden cushion block 1', adapted directly to receive theblow from the hammer. The casing and the follower are provided with means (not shown) to engage the vertical hammer guides (also not shown) and assist in iding the pile when the latter is sunk. hen the hammer is in operation its blows are transmitted to the pile through the plunger 1, cushioning body 0, diaphragm m and the lock n, the cushioning body at each blow of the hammer yielding sufficiently to i the plunger 1) to cushion the blow and revent injury to the hammer. During (riving, water may --be freely admitted to the jetting pipe without interference with the driving a'paratus. In some cases it may be deslrab ie to enter the water at some point below the top thereof instead of between the end'and the driving apparatus. This may be readily accomplished, as is shown in form of my invention, it is to be understood that I am not limited to the details or the form or relative. arrangement of parts disclosed, but that extensive modifications may be made therein, without departing from the spirit thereof.

--Claims 1. A- concrete pile having the cross-section of a regular polygon, an interior water induction passage and a plurality of exterior water eduction passages affording substantiallyequal resistance, to the passage of water.

.2. A concrete pile having a hexagonal cross-section, an interior central jetting passage and a plurality of exterior grooves in the pile sides symmetrically arranged with reference to the jetting passagel. v

3.'A tapered concrete ile having the cross-section of aregular po ygon, an interior induction jetting passage and eduction grooves in the sides 'of the pile symmetrically arranged with reference to the outlet and the jetting passage. v 4. concrete pile having an interior downwardly directed jetting passage and corrugated or grooved sides, the 'corru ations or grooves terminating short of t e leading end.

v5. A- concrete pile having a substantially similar cross-section from end to end and provided with grooved sides,'the corrugations or grooves extending a portion of the pile length onl 6. Thecoin ination with a concretepile having an interior induction passage, of a removable jetting pipe extending substantially the length of said passage.

7. The combination with a concrete pile longitudinal edges thereof.

14. A concretepile having a reinforcement 8O tion of a regular polygon, central independent reinforcing means, and reinforcement also for thecorners of said pile.

12. A concrete pile having the cross-section of a regular polygon, and independent reinforcement immediately adjacent the longitudinal edges thereof.

13. A concrete pile havin plane sides, central reinforcing means and independent reinforcement immediately adjacent the comprising a plurality of longitudinal .rods, members arranged at' intervals unitin the same in a com osite structure, and additional separate rein orcing' rods outside of said composlte structure- 15. A tapered concrete pile having the cross-section of a regular (polygon and a plurality of exterior longitu inalgrooves.

v 16. A tapered concrete pile having a horizontal cross-section of a regular polygon and a lurality of half-round exterior longij tudina grooves.

17. A concrete pile'havingy the cross-sec-v tion of a regular' olygon and provided with a plurality of s'u stantially half-round ex-.

terior longitudinal. ooves extending part way only the lengti l ofthe pile, said pile being formed .with a substantially uniform taper from one end to the other-.

18. A concrete pile having the cross section of a regular polygon and provided in each side face with a half round exterior longitudinal groove extending part way only the" length of the pile, an interior axially arranged jetting passage havingan outlet at the leading end of the pile, and an interior com osite tapered reinforcing structure for the ody of the pile, said pile being formed end tolthe other.

19. A concrete pile having means permitting the production of a forwardly directed water et at the leading end of .the pile and having also a plurality of well defined, longitudinal ooves in the sides of the pile, said grooves eing of suitable-formation to return the water therethrough. 20. A concrete pile having means p erm1tting the production of a central water jet at the leading end of the ile and having also a plurality ofwell-define longitudinal grooves in the sides of the pile located symmetrically With a substantially uniform taper from one i with reference to the jet at the leading end I having means ermitreturn the jetting water up the sides of the. j

pile in unobstructed streams, said grooves eing so formed and located that the minimum distance from the pile axis to the side thereof lies through the said grooves.

22. A concrete pile-having means permitting the production of a water jet at the leading end of the pile and having also at least four longitudinal grooves arranged about its sides and adapted to return the jetting water in unobstructed streams.

23. A concrete pile having 'etting means at the forward end thereof and aving means for returning the water to the surface with a substantial minimum of frictional resistance and in a series of unobstructed streams.

24. A concrete. pilehaving etting means at the forward end thereof, and having means for returning the water to the surface with a substantial minimum of frictional re- 4 sistance and in a plurality of streams of submeans at the forward end thereof, and having means upon each face thereof for returning the water to the surface in compact streams having substantially equal erosive capacity.

27. A concrete ile having longitudinal grooves upon its sic es and forwardly direct- "ed jetting means at the leading end,-said grooves being shaped to provide return Water passages of lowfrictional resistance,and symmetrically disposed with respect to the jet, whereby substantially equal erosive action is secured about the pile.

28. A concrete pile having longitudinal grooves u on its sides and a central water jet at the lea ing end, said grooves being shaped to permit the jetting water to encounter a low frictional resistance in returning to the surface, and being arranged concentrically with respect to said jet, whereby substantially equal erosive action is secured about the pile and the same will sink substantially vertically.

29. A concrete pile rovided at its leadin end with a forwardly irected water jet and upon its sides with a series of longitudinal grooves which are shaped to permit the jetting water to return to the surface thereto with a substantial minimum of frictional resistance, whereby an effective erosive action is secured.

30. A concrete pile having the cross sec-' tion of a regular polygon, central reinforcing means, and reinforcing means for the corners of the pile, said pile having longitudinal exterior grooves.

31. A concrete pile having the cross section of a regularpolygon, and reinforcement immediately adjacent the longitudinal edges thereof, said pile having longitudinal grooves upn the surface thereof.

In testimony whereof, I have signed my name to this specification, in the presence of two subscribing witnesses.

FRANK B. GILBRE'IH.

Witnesses: I

THOMAS B.Boorn, EDITH E. CHAPMAN. 

